The purpose of this core is to pursue and support the investigation of sex- specific factors in nicotine-dependence and treatment. The function of the core is supported by an emerging empirical literature, and by national research goals. The core will support all Center investigators, and it will be linked to other institutional programs at Yale in order to enhance transdisciplinary collaboration. Although the core will initiated independent projects, its primary mission will be cost-effective attention to sex-specific factors in current and new projects through such means as pooling data to test sex-related hypothesis, including assessments related to sex and gender issues, ensuring adequate representation of women so that sex related comparisons can be made, and taking charge of data analysis and interpretation of findings pertaining to sex differences for all appropriate Center projects. Improvement in the health of women and men depends upon new-found scientific knowledge which recognizes sex-specific effects. The core is directed toward strengthening existing research in nicotine dependence as it relates to sex and gender, and developing new, cutting-edge areas of investigation that will result in direct practical benefit. The specific aims of the core are as follows; 1) Testing sex-specific models of smoking maintenance 2) Assessing sex-specific benefits of smoking cessation. 3) Investigating the relationship of sex-specific hormonal factors to treatment response and relapse. 4) Providing support and methodological consultation to investigators examining sex and gender effects in Center projects.